Closure control mechanism



May 23, 1961 V.1. K. KRAFT cLosURE CONTROL MECHANISM 2 Sheets-Sheet 2 Filed Dec.

Fig. 2

mvENToR Joseph K. Krof1` ATTORNEY Fig. S9Wl swa nited States Patent O CLOSURE CONTROL MECHANISM Joseph K. Kraft, Verona, NJ., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Dec. 17, 1957, Ser. No. 703,382

1 Claim. (Cl. 187-52) This invention relates to closure control mechanism and it has particular relation to controls for the doors of elevator systems.

Although aspects of the invention are applicable to closures designed for various applications, the invention is particularly suitable for closures or doors employed in elevator systems. Consequently, the invention will be described with particular reference to elevator closures or doors. Furthermore, aspects of the invention are applicable to doors of various types such as center-opening, side-opening, single-speed and two-speed door assemblies. For the purpose of discussion, however, reference wi-ll be made lto door assemblies of the center-opening type as employed in elevator systems.

In `addition to the car door, a separate hoistway door is generally provided for each of the landings or floors served by an elevator car. It is conventional practice in elevator systems to employ a master door operator mounted on the elevator car for operating hoistway doors. When the car is located at a landing, the master door operator is coupled releasably to an associated hoistway door for the purpose of opening and closing the hoistway door. Male and female devices or members may be employed for coupling the master door operator to a hoistway door. The female device may take the form of a slotted device or drive block and the male member or device may take the form of a vaned device having a vane which is receivable in the slot of the slotted device. Conveniently, a separate one of the drive blocks is secured to each of the hoistway doors while the vane is operable by the master door operator and may be secured to the car door. Consequently, when the car is located at a landing and the slot receives the vane of the vaned device, operation of the master door operator to move the car door and thus the vane effects a corresponding movement of the hoistway door.

With the above arrangement, under certain conditions there is danger of lateral displacement of the vane from its normal position of alignment with the slot. Consequently, as the elevator car travels verticallyin the hoistway 'the vane may strike the slotted device, causing damage to either or both the vane and one of the slotforming elements of the slotted device.

Alternatively, the vane may be laterally displaced by distance suiciently great to preclude either alignment with the slot or contact with one of the slot-forming elements as the car travels vertically in the hoistway. Since the vane is then positioned outside of the hoistway door drive block, normal door operation cannot be `effected when the car is located at a landing. The elevator car thus cannot leave the floor, and the car is thereby taken out of service until the fault is corrected manually.

In accordance with the invention, the slotted device is provided with the pair of slot-forming elements constructed of substantially non-resilient material. The elements are independently rotatable about vertical axes. Should the situation cited in the previous paragraph ice occur, one of the elements is rotated in a horizontal plane about its axis by force of the vane When the latter is actuated by the master door operator. Such action allows the slot to receive the vane, after which the rotated element is returned to its normal position by biasing means. The doors may then be operated in Ia normal manner. The vane and the drive block are so congured that if the vane is in position to strike one of the slot-forming elements as the elevator car travels vertically in the hoistway, the element so struck will be rotated about its axis suiciently to allow movement of the vane relative to the slotted device Without damage to either.

In accordance with a further aspect of the invention, a center-opening door is provided With a door operator and object-detecting means for detecting the presence of an object substantially in the closing path of movement of the door. Each section of the door is furnished with an object-detecting device which is positioned adjacent that edge of its associated door section which is a leading edge during a door-closing operation. The object-detecting devices cooperate with the door operator to sense the presence of objects in the closing path of the door in sufficient time to stop or to stop and to reverse the door before an objectionable impact can take place between the door and an object.

The object-detecting devices may be associated with hoistway doors or car doors of an elevator system, If the elevator system has both car and hoistwayvdoors, the object-detecting devices convenient-ly may be associated with the car door and may be positioned in the space normally provided between the car and hoistway doors. When so positioned, the object-detecting devices provide substantial protection for both the car and hoistway doors, particularly when the doors are moved as a unit as previously set forth.

Both object-detecting devices lead their associated door sections during a substantial closing movement of the door. One of the object-detecting devices is adjusted in position in accordance with the position and movement of the door section with which it is associated. As the door nears the completion of its closing movement, the adjustable object-detecting device is moved to a retracted position relative to its associated door section and is retained in such retracted position When the door is in closed position. The retraction is sufficient to prevent operation of one of the object-detecting devices by the other, the device which does not retract remaining sensitive to detect obstructing objects at all times.

When the door is in fully-open position, each objectdetecting device preferably projects into the `entranceway so as to be in full view and readily accessible for use; and each device remains sensitive so that the door may be retained in open position by application of relatively small force to either of the object-detecting devices. The distance by which each object-detecting device projects into the entranceway when the door is in fully open position is suiiciently small to prevent reduction of the clear opening when the door is in fully-open position by an objectionable amount.

It is, therefore, a first object of the invention to provide Ian improved door operating mechanism comprising a master door operator and cooperating-male and female device or members.

It is a second object of the invention to provide a door operating mechanism as set forth in the preceding paragraph wherein the male and female devices may be brought into cooperative engagement upon operation of the master door operator if said devices are initially displaced laterally from one another.

It is a third object of the invention to provide door operating mechanism as set forth in the previous paragraph wherein the 4female device takes the form of a slotted device having a pair of slot-forming elements which are constructed of substantially non-resilient material and which are independently deilectable in a horizontal plane and the male device takes the form of a vaned device having a vane which is receivable in the slot of the slotted device.

It is a fourth object of the invention to provide an elevator system having an elevator car wherein a master door operator carriedfby the vcar has a vaned device having a vane normally positioned -for releasable reception in the slot of a slotted device of the type set forth in the preceding paragraph carried by each of a plurality of hoistway `doors and wherein vertical movement of the vane relative to the slotted device may be translated to horizontal dellection of one of the slot-forming elements to prevent damage to either device.

It is a ft-h object of the invention to provide a system as dened in the preceding paragraph wherein the vane has -upper and lower surfaces which are tapered toward the slotted device when the elevator car is located opposite a hoistway door.

I It is a sixth object of the invention to provide a closure system having an improved object-detecting device.

It is la seventh object of the invention to provide a closu-re system having a door and object-detecting-means comprising a pair of object-detecting devices wherein a separate one of the devices is adjustable to various positions in accordance with the position and movement of the door.

It is .the eighth object of the invention to provide a closure system as dened in the preceding paragraph wherein the object-detecting devices are relatively movable toward one another in the same plane during a doorclosing movement and the adjustable object-detecting device is moved to a position preventing engagement between the object-detecting devices as a door-closing movement is completed.

It is a -ninth object of the invention to provide a dualsection center-opening door having object-detecting means comprising an object-detecting device for each door section wherein each device is movable in the same plane and is maintained in a leading position with respect to its associated door section during at least VIa major part of the door-closing movement yand in which a separate one of the devices is retracted to a less' leading position with respect to its associated door section as the door completes its closing movement to prevent operation of one of the devices by the other.

It is the tenth object of the invention to provide a door as set forth in the preceding object wherein said one device is retained in its retracted position with respect Vto its associated door section when the door is in closed position.

It is the eleventh kobject of the invention to provide a door as set forth in the ninth object wherein the objectdetecting means remains sensitive to the position of an object relative to the door during the entire closing movement of the door.

Other objects of the invention will become apparent from the following description taken in conjunction with the accompanying drawings, in which:

Figure l is a view in elevation, with parts in section, parts broken away and parts schematically shown, of an elevator system which mayv incorporate the invention;

Fig. 2 is a view in front elevation, with parts broken away, of an elevator car having a closure system embodying the invention;

Fig. 3 is a view taken along the line III-III of Fig. 2, with parts broken away, wherein the elevator car of Fig. 2 is shown in association with a portionof the hoistway enclosure;

Fig. 4 is a sectional View taken along the line IV-IV of Fig. 2, with parts broken away, with a portion of the associated elevator hoistway enclosure added;

Fig. 5 is a view similar to the View of Fig. 4 wherein the elevator car door and associated hoistway door are shown in open position;

Fig. 6 is a detailed view in front elevation of an elevator door drive block embodying the teachings of the invention;

Fig. 7 is a top plan view of the drive block of Fig. 6 shown in association with a portion of a vane and -a mounting bracket;

Fig. 8 is a view in side elevation, with portions broken away, of the vane illustrated in Fig. 7 with a portion of its associated door; and

Fig. 9 is a schematic View of an electrical system suitable for operating the closure of Fig. 2.

Referring to the drawings, Fig. 1 shows an elevator system which includes a hoistway enclosure l for an elevator car 3. This elevator car may serve any desired number of floors or landings but to simplify the illustration only floors l and 2 of the building `are shown associated with the hoistway. The elevator car is connected to a counter-weight 5 by means of flexible roping or cable 7 which passes over a sheave 9. This sheave is rotated by a suitable control mechanism 11 for the purpose of reciprocating the elevator car in its hoistway and stopping the elevator car at any desired landing. A car switch 13 positioned in the car and suitable push buttons l15 may be provided for each door in a conventional manner `for initiating movement of the elevator car to any desired door. Since suitable control mechanisms for elevator cars are understood in the art, a further discussion thereof is unnecessary for an understanding of the invention. Y

At each floor the hoistway enclosure is provided with |a hoistway door 17. In addition, the elevator car has a door 19 which, when the elevator car is stopped at a floor, is aligned with the associated -hoistway door. As mentioned above, thervarious doors may be of any desired conventional construction, such as center-opening or sideopening doors, or double or single doors. For purpose of illustration, it will be assumed that the doors are center-opening doors mounted for horizontal sliding movement.

Although the elevator car door 19 could be operated manually, a door operator mounted on the elevator car is employed vfor opening and closing the car door to expose and to close an elevator car entranceway 19a, through which passengers enter and leave the car. Such an operator is shown in Fig. 2 and now will be described.

The center-opening car `door 119* comprises two sections 20 and A20. In Fig. 2 the door 19 i-s Vsho-wn in closed position. VA number of similar components is employed for the door sections 20 1 and A20. luso-far as as practicable, a component for the door section A20 which is similar to a component for the door section 20 will be identified by rthe same reference numeral asis employed for the corresponding'component associated with the door section 20, preceded bythe letter A.

The door section 20 'is provided with a door hanger 23, on which door hanger wheels 2S are Ymounted for rotation. The `door hanger wheels for the door sections 20 and A20 are positioned for 4movement along a horizontal- Ily-mounted track 27 in a conventional manner. The track 27 'is secured to theV elevator car 3. Y

Movement of the door section 2.0 is effected by a lever 29 which is pivotally mounted on the elevator car 3 by means of a pin 31. The lower end of the lever 29 is pivotally connected to one end of a link 33, the other end of the link'being pivotally conneotedto the door section 20. By inspection of Fig. 2, it will be observed that the lever 29 is coupled to the lever A29 by a link '35 which has its endsY pivotally attached to the levers 29 and A29, respectively, Vbypivots 37 and A37. It will be observed that the pivot 37 is positioned above the pin 31 whereas the pivot A37 isV located below the pin A31.

Consequently, rotation of the lever 279' to open the Ydoor Y 'section 20 moves the link 35 in the proper direction to open the door section A20.

The lever 29 preferably is operated by a suitable door operator 39 which may include a reversible electric motor `41 coupled `through suitable gearing to a shaft 43. The shaft 43 carries an `arm 45 which is pivotally connected to one end of a link 47, the remaining end of the link 47 being pivotally connected to the lever 29. Consequently, the motor 41 may be energized in a conventional manner for the purpose of opening and closing the door sections. When the door 19 is to be opened, the motor 41 is operated to rotate `the arm 45 in a clockwise direction as viewed in Fig. 2. In order to reclose the door the electric motor is reversed and returns the arm 45 to the position illustrated in Fig. 2.

It is conventional practice to provide the hoistway enclosure 1 in which the elevator car 3 operates with a hoistway door at each landing served by the elevator car which is similar to the door 19 of the elevator car. For example, in Fig. 3 the hoistway enclosure 1 in which the elevator car 3 operates is provided with the door 17, as heretofore pointed out, for a hoistway opening 48 for each landing served by the elevator car. Thus, the door 17 comprises door sec-tions 49 and A49 which are similar to the door sections 20 and A20, respectively, of the elevator car (see also Fig. 4). The Ihoistway door section 49 is -mounted on hanger wheels 50 which operate along a horizontal track 51 secured to the hoistway wall. Similar hanger wheels (not shown) are provided for the hoistway ydoor section A49. The hoistway door sections 49 and A49 are also interconnected by levers and links similar to those described for the car door sections 20 and A20.

Referring now to Figs. 4 through 8, the `door operator employed for opening and closing the elevator car door I19 is also employed for opening and closing each of the hoistway doors 17 served by the elevator car. To this end cooperating male and female members or devices are provided on the elevator car door and on each of the associated hoistway doors. Prefarbly the male member in the form of a vane 52 of any suitable material, such as steel, is secured in any suitable manner to a vane base 53 which is in turn secured to the car door section 20 by means of bolts 54. Each of the hoistway door sections 49 is provided with a female `device in the form of a slotted drive block 55 for reception of the vane 52. As is shown in Fig..8, the vane 52 is elongated in the direction of travel .of the elevator car.

The 4slotted device or drive block 55 has a base portion 56 and a pair of oppositely disposed rotatable elements or fingers 57 and 57a. A number of similar components is employed for the elements 57 and 57a. Insofar as is practicable, a component for the element 57a which is similar to a component for the element 57 Will be identified by the same reference numeral as is employed for the :corresponding component associated with the element 57, -followed by the letter a.

The element 57 is rotatable in a horizontal plane about the axis of a pin 59, which extends in the direction of car travel. The pin 59 extends through an aperture in the element 57, as is clearly shown in Figs. 6 and 7, and may be secured to the element in any suitable manner such as by a press iit. The ends of the pin 59 extend through apertures 62 in a pair of hubs 61, which conveniently may be formed of the `same material as that from which the base portion 56 is formed. The apertures 62 -have diameters which allow the pin 59 to rotate about its axis freely therein, but which are suiiiciently small to prevent appreciable movement of the pin 59 in other directions. The element 57 also has a curved slot 63 through which extends a pin 65 which is similar to the pin 59. The ends of the pin 65 extend through apertures in the hubs 61. The pin 65 may be secured to the hubs 61 in any suitable manner such as by a press fit. The ends 67 and 67a of the fingers 57 and 57a, respectively,

are spaced apart and proportioned to form a s-lot 69 for reception of the vane 52. The element ends 67 and 67a are biased away from each other by biasing means in the form of a spring 711, the ends of the spring 71 extending through apertures 73 and 73a which are formed in projections 74 and 74a of the lingers 57 and 57a respectively. The pins 65 and 65a act as stops to posi-tion the elements 67 and 67a as shown in Figs. 6 and 7, the pins 65 and 65a cooperating -vvith the slots 63 and 63a, respectively, for this purpose. IIt will thus be seen that the element 57 is rotatable in a lclockwise direction while the element 57a is rotatable in a counterclockwise direction from their respective positions shown in Fig. 7.

The base portion 56 of the drive block has extensions 75, each extension having an aperture in the form of a slot 77. The drive block 55 is secured to a bracket or plate 78 by means of bolts 79, each of which. passes through the plate, a plurality of shims y31, one of the slots 77, a washer 83 and into a nut 85. The bracket 78 is in turn secured `to the hoistway door section 49 by any suitable means such as by a plurality of bolts (not shown). The shims 81 permit adjustment of the drive block 55 perpendicular to the hoistway doo-r section 49 and the slots 77 permit adjustment of the `drive block parallel to the hoistway ydoor section 49. Such adjustments are provided to permit proper location of the `drive block for cooperation with the vane 5-2 of the car door section 20. The vane 52 may have any suitable dimensions which will enable it to be received by the slot 69 when t-he elevator car door 19 is positioned opposite the hoistway door 17.

During reciprocation of the elevator car 3 in its hoistway 1, the vane 52 normally occupies the position illustrated by the solid lines in Fig. 7. Under such conditions substantial clearance is provided between the vane 52 and the drive block y55 of each hoistway door to permit free passage of the vane through each of the slotted devices. When the elevator car is stopped at a floor for the purpose of discharging or receiving passengers, the motor 41 is energized to initiate a door-opening operation. When the door section 20 of the elevator car is thus moved, the vane 52 engages the element end 67 of the drive block to effect a corresponding opening movement of the hoistway door section 49. As explained above, by operation of the levers and links interconnecting the car door sections 20 and A20 and those interconnecting the hoistway door sections 49 and A49, the sections A20 and A49 `are also opened. In order to effect a door-closing operation, the shaft 42 of the motor 41 is caused to rotate in the opposite direction, which causes the vane 52 to engage the element end 67a. The door sections then move in directions opposite their directions of movement during the door-opening operation.

It will be recalled that the vane 52 is normally positioned for reception by the slot 69', as is shown by the solid lines in Fig. 7. Under certain conditions, however, the vane may be displaced laterally so as to be in a position in which the slot 69 does not receive the vane. For example, it is conventional practice to provide the elevator car with an emergency stop button (not shown). A passenger may push this button as the car leaves a floor. The car may have moved suiliciently so that the vane has disengaged the drive block slot. The c-ar door opens, and the car is caused, by operation of suitable control means, to reapproach the landing. The vane is now positioned outside of the drive block, as is shown by the broken lines in Fig. 7. Upon energization of the motor 41 to effect a door-closing operation, the vane 52 is moved suiciently to engage the drive block element 57. As the vane continues to move, it exerts a force on the element 57, causing the element to deilect in opposition to the biasing spring 71, as is shown by the broken lines in Fig. 7. Such deflection of the element continues until the vane reaches a position in which the vane and the element disengage, the element 57 being returned to its normal position by means of the force exerted by the spring 71. Thereafter, normal operation of the car and hoist- Way doors may be effected.

Another situation may arise wherein the vane 52 may be displaced laterally from alignment with the slot 69 but in position to strike one of the drive block fingers as the elevator `car travels vertic-ally in thehoistway. It is then desirable that the finger so struck be deflected in a manner which prevents damage to either the vane or the drive block. To this end the vane and the drive block fingers are so configured that relative vertical movement of the two members may be transferred to rotation of one of the fingers. In a preferred embodiment, the upper and lower surfaces of the vane 52 are tapered toward the drive block 55, as is clearly shown in Fig. 8. It will thus be seen that when the vane strikes one of the slot-forming elements during vertical car travel that element will be deflected in opposition to the biasing means 71 to a position which allows passage of the vane past the element, while preventing damage to either.

A combination of the two above-mentioned situations may occur when the car approaches a landing for a stop to permit the discharge or entry of passengers, i.e., the vane may be laterally displaced from its normal position of alignment with the slot, while at Vthe same time engaging one of the slot-forming elements before a dooropening operation is initiated. In this instance, vertical movement'of the vane will first cause deection of the element with which it is engaged, by virtue of its taper, to permit the car to stop at its normal position at the landing. Thereafter, initiation of a car door-opening operation will cause the vane to deflect the element with which it is engaged sufficiently-to enable the slot 69E to receive the vane in he manner described above. Thus, no matter how much the vane is displaced laterally from its normal position of alignment with the slot, damage to both the vane and the drive block is prevented; and normal operation of the car and hoistway doors may be effected without taking the elevator Icar out of service in order to correct the fault manually.

The invention as thus far described has several additional advantages. 'I'he drive block is small and compact and may be made at relatively low cost. The elements 57 and 57a may berconstmcted of long-wearing material having a self-lubricating property, such as nylon. It will be observed that, with ythe drive block construction herein disclosed, the hoistway and car doors may be operated independently of one another as an aid to servicing and maintenance of the doors, since one of the drive block elements 57 may be deflected manually, after which one of the doors may be moved sufficiently to disengage the vane from the drive block slot.

It should be noted that the positions of the drive block and the vane may be reversed without essentially affecting operation of the invention; i.e., the drive block may be carried by the elevator car, while each hoistway door may be provided with a van receivable in the slot of the drive block. Y

While the drive 'block described herein has been shown in association with a single-element vane, is may be used with an expansible vane member, such as is described in the Rissler et al. Patent 2,502,995 or with other suitable vanes known in the art.

During closing movement of the doors one or more objects may be located in theY closing paths of the doors. To prevent undesired impact between the doors and such an obiect, the elevator car door sections 20 and A241 are provided with object-detecting devices 91 and A91, respectively. Each of the object-detecting devices is located adjacent that edge of .its associated door section which is the leading edge during a closing operation of the door (Figs. 2, 4 and 5).

As previously pointed out, each of the object-.detecting the edge of the associated door section which is the leading edge during door closure. For example, in Fig. 2 the object-detecting devices 91 and A91 include objectydetecting elements 92 and A92, respectively. As is shown in Figs. 4 and 5, each detecting element may take the form of a nosing having a channel con'guration. Preferably the web of the channel is rounded, as is illustrated in Figs. 4 and 5. The nosing may be constructed of any suitable material such yas plastic or rubber. A lightweight plastic such as a phenolic resin is very satisfactory. A nosing of such material may be cemented or secured to a support member of rigid, lightweight material such as aluminum. Alternatively, the nosing itself may be constructed of a lightweight metal such as aluminum. It is desirable that the weight of the detecting element be as light as practicable in order to obtain maximum objectdetecting device sensitivity. Since this type of detecting element construction is well known in the art, it appears unnecessary to described it further.

The detecting element 92 is pivotally secured to the door section 20 by means of levers 93 and 95. Qne end of the lever 93 is connected to the detecting element 92 by means of a pivot 97. Similarly, one end of the lever 95 is connected to the detecting element 92 by means of a pivot 99. The other ends of the levers 93 and 95 are connected to back plates 101 and 103, respectively, by means Vof pivots 105 and 107. The back plates 101 and 103 are secured to the door section 20 by a plurality of bolts 109. As is shown in Fig. 2, the levers 93 and 95 are parallel to one another, extending upwardly angularly toward the meeting point of the door sections. Movement of the detecting element 9.2 eifects Vcorresponding movements of the levers 93 and 95, the levers remaining substantially, parallel to'one another in all positions of adjustment of the detecting element. It will be observed, therefore, that the detecting element remains substantially parallel to the adjacent edge of the door section 207m all such portions of adjustment.

Movement of the levers 93 and 95 is limited byrsuit-V able stops. For example, clockwise movement of the lever 93, asviewed in Fig. 2, is limited by a stop or bumper 111, while counterclockwise movement of the lever 95 is limited by a stop or bumper 113.V The stops 111 and 113 are secured as by cementing to brackets 115 and 117, respectively, the brackets in turn being secured to the back plates 1,01 and 103 as by screws 118. Thus, the detecting element 92 is biased in an upward direction by means of the stop 111; and total movement of the levers 93 and 95 and, therefore, of the detecting element 92 is limited by the stops 111 and 113. The stops may be of any suitable material, such as sponge rubber, for absorbing the kinetic energy of the moving detecting element 92.

The object-detecting device 91 includes translating means responsive to theposition of an object relative to the door section 20. Conveniently, the translating means may vcomprise a sensitive electric switch 119 which is biased toward Vopen condition. Movement of the lever 95 is employed for operating the switch 119. The switch 119 has a switch-operating member 121 Vwhich projects from the body of the switch. The switch-operating member may be in the ,form of a leaf spring. The switch 119 is suitably secured to the back plate 103 in a position such that Vits operating member 121 may be engaged by the leverr95. Thus, when the detecting element 92 is in the position shown in Fig. 2, the :lever 95 exerts a force on the switch-operating member 121 such that the switch 119 is actuated to closed condition. Should a force by an obstructing object be exerted on the detecting element 92, the lever v95 will rotate in a counterclockwise direction, as Viewed in Fig. 2,V the force exerted by the lever 95 on the member 121 willV t e ment 92 relative to the door section 20 may cause the switch 119 to be actuated by means of the lever 95.

It will be seen upon inspection of Figs. 4 and 5 that, unless otherwise provided for, the detecting elements 92 and A92 Will be brought into engagement with one another as the door 19 completes a door-closing movement, thereby causing the `object-detecting devices to operate each other. To prevent such operation, means are provided for retracting and detecting element A92 to a less leading position with respect to its associated door section A20 as the door completes a closing movement. Such retracting means may comprise a flexible chain or cable 133 and a roller 135. One end 137 of the cable 133 is suitably secured to the detecting element A92. The other end 139 of the cable 133 is fastened in any suitable manner to a bracket 141 which is in turn fastened to the sill 143 of the elevator car 3 as by bolts 145. The roller 135 is rotatably mounted on `the door section A20 by means of an axle 147, the roller having a peripheral groove for reception of the cable 133.

When the door 19 is in closed position, the cable 133 is pulled taut causing the detecting element A92 to be positioned as is shown in Fig. 2. As the door starts to open, the cable 133 slackens and, due to the force of gravity, the detecting element A92 moves toward a trailing position With respect to its associated door section A20. Upon continued opening movement of the door section A20, and further slackening of the cable 133 thereby, the detecting element A92 moves suiciently to bring the lever A93 into engagement with the bumper A111. During the remaining portion of the door-opening movement, the detecting element A92 maintains the position, relative to the door section A20, eiected by enagement of the lever A93 with the bumper A111. The detecting element 92 maintains a trailing position with respect to its associated door section 20 during the entire door-opening movement. These positions of the detecting elements 92 and A92 relative to their associated door sections are shown in Fig. 5, wherein the car and hoistway doors are illustrated in fully open position. A slack-cable guard 149 suitably secured to the door section A20 prevents the slack cable 133 from escaping from the peripheral groove of the roller 135. During substantially the entire closing movement of the doors, both of the detecting elements 92 and A92 remain sensitive to detect any object which may obstruct the closing paths of the movement of the doors.

It will be clear from Figs. 2, 4 and 5 that when the elevator car is located at a landing the object-detecting devices 91 and A91 are located substantially between the elevator car door 19 and the associated hoistway door 17. Consequently, the object-detecting devices provide protection for both of the doors with respect to objects Which are substantially in the closing paths of the doors. This is particularly true of car and hoist- Way doors which are opened and closed in unison as by the male and female coupling devices here shown. Furthermore, when the doors are closed, the objectdetecting devices are substantially concealed and protected by the doors. IIn addition, it will be observed that the detecting element 92, which does not retract, remains sensitive at all times. The detecting element 92 overlaps the meeting point of the door sections when the doors are in closed position and thus is operative to detect any size of obstruction, no matter how thin, that may be caught between the door sections as they complete a closing movement.

When either detecting element initially engages an object in the closing path of the door, such element is brought to a stop. Since the element is extremely light in weight and since it operates comparatively few parts during the movement thereof, extremely sensitive objectdetecting devices are provided. It is immaterial, of course, whether the detecting element A92 or the detecting element 92 is retracted when the doors are in closed position. Consequently, the retracting means may beV associated with the detecting element 92 rather than with the detecting element A92 as is illustrated.

Conveniently, the detecting elements 92 and A92 may project beyond their associated door section edges when the door sections are away from closed position by a distance of the order of one to one and one-half inches. Such projection is preferably as small as practicable, in order to compromise for the reduction of the clear opening when the doors are in fully-open position. Preferably, the detecting devices remain sensitive when the doors are fully open so that the doors may be held open by a passenger, who is required to exert a relatively small force on one of the detecting elements for this purpose. As pointed out above, each object-detecting device may be so constructed that movement of as little as onequarter inch of either nosing is suicient to cause the doors to be held open. Each detecting element may project as much as two inches or more beyond its associated door-section edge toward the elevator door entrance- Way if the door sections retract behind their associated door jamb lines when the doors are fully open, so that the projecting elements do not reduce the clear opening by an objectionable amount. It should be borne in mind that the elements preferably should project into the entranceway, so that they are in full View and readily accessible for use when the doors are in fully-open position.

In order to illustrate suitable operation of the electric switches 119 and A119, a simple schematic diagram is shown in Fig. 9. In this diagram, the armature 41A and the field winding 41F of the ldoor operating motor 41 (Fig. 2) are illustrated. The switches 119 and A119 are connected in series with the energizing coil of a doorsafety relay DR across the direct current buses L+ and L Consequently, as long as the switches 119 and A119 remain closed, the relay DR remains energized and picked up to close its make contacts DRI, DR2 and DR3 and to open its break contacts DR4. Under normal conditions, the motor is energized to open or to close the doors by operation of a switch SW. Although this may -be a manually operated switch, in a preferred embodiment of the invention, this switch represents the contacts of a relay or relays employed in any conventional dooroperating system -to initiate an opening or a closing operation of the doors. Assuming that the doors initially are in their open condition, movement of the operating member of the switch SW up results in closure of its contacts SW1 to complete with a limit switch 151 and the contacts DRS a circuit connecting a door-closing relay CL across the buses L+ and L for energization. The relay CL closes its contacts CL1 and CL2 to complete the following energizing circuit: L+, DR2, CL2, 41F, CLI, DRI, 41A, L This circuit energizes the motor for operation in the door-closing direction. As the doors near their fully-closed condition they open the limit switch 15.1 to interrupt the energizing circuit for the door-closing relay CL. This relay thereupon drops out to terminate the energization of the motor 41.

If the doors are to be opened, the operating member of the switch SW is operated down to close its contacts SW2. These contacts, together with a limit switch 153, complete an energizing circuit for a door-opening relay OP. Consequently, the relay closes its contacts OP1 and CP2 to complete the following circuit: L+, OP1, 41F, OPZ, 41A, L The motor now is energized in the proper direction to open the doors. As the doors near their fully-open position, the limit switch 153 opens to deenergize the door-opening relay OP. This relay opens its make contacts OPI and CP2 to deenergize the eld winding 41F and the armature 41A.

Let it be assumed that during a door-closing operation an object in the closing path of the car door 19 engages the detecting element 92 of the detecting device 91 to operate the switch 119. The resulting opening of the switch 119 deenergizes the door-safety relay DR (Fig. 9) and this relay thereupon opens its malte contacts DR1 and DR?. to deenergize the eld winding 411? and the motor armature 41A. Consequently, the doors are brought to a stop. Contacts DRS also open to interrupt the energizing circuit for the door-closing relay CL. If desired, the deenergization of the door-safety relay DR may also be accompanied by reopening of the doors. To this end, break contacts D114 are provided which are closed when the door-safety relay DR is deenergized to complete with the limit switch 153 an energizing circuit for the door-opening relay OP. It will be observed in Fig. 9 that the switch A119 operates in a manner similar to that described for the switch 119.

When the door sections Ztl and A29 near the completion of a door-closing movement, the detecting element A92 is retracted by an amount suicient to cause the switch A119 to be opened, at which time the contacts of the switch A119 are shorted by the closed contacts of a mechanical interlock switch 161 (Figs. 2 and 9). Conveniently, movement of the door section A211 may be utilized to operate the switch 161, which is biased to open position. To this end, a cam 163 is secured to the door section hanger A23 for the purpose of engaging a cam follower of the switch 161 to close the contacts of the switch 161. As a door-opening movement is initiated and the detecting element A92 moves by an amount suiiicient to close the contacts of the switch A119, the cam 163- disengages the cam follower, and the contacts of the switch 161 open. Such operation of the switch 1611 prevents the doors from reopening when the detecting element A92 is retracted, while allowing the objectdetecting device A91 to be sensitive at all other times.

Although the invention has been described with respect to specific embodiments thereof, numerous modications falling within the Spirit and Vscope of the invention are possible.

I claim as my invention:

In an elevator system, an elevator hoistway enclosure Y having a hoistway door therein, means mounting the door for horizontal reciprocation between open and closed positions, an velevator car disposed for vertical movement in the hoistway enclosure from a position displaced from the door to a predetermined position adjacent the door, door-operating mechanism disposed on the car, a slotted device having a vertically extending slot, and a vaned device, one of said devices being secured to the door for movement therewith and the other of said4 devices being carried by the elevator car and being Operable by the' door-operating mechanism in the direction of door movement, said vaned device including a vertically extending vane normally disposed for reception in the slot of the slotted device when the elevator car is in the predetermined position, said slotted device havng a base structure and a pair of oppositely disposed elements mounted for independent movement relative to the base structure respectively about spaced vertical axes, each of said elements having an end which is spaced from the associated axis and from an end of the other element to form said slot, biasing means biasing said ends relative to the base structure towards slot-forming positions, said biasing means comprising a horizontally-extending helical spring disposed substantially parallel to said door and coupled to each of said elements at a point between its respective axis and said base structure, and stop means for preventing movement of said elements in the biased directions beyond said slot-forming positions in opposition to said biasing means, said vane in response to operation of said door-operating mechanism when the car is Vin said predetermined position and said vane is disposed in said slot engaging said element ends alternately in opposition to said stop means to effect respective alternate opening and closing movements of said door, said elements and the vane being configured to permit said vane in opposition to said biasing means to rotateythe element nearestV it suiciently to enable said slot to receive said vane upon operation of said door-operating mechanism when said vane is displaced from said slot in a direction of door movement upon arrival of the elevator car at the predetermined position,rsaid biasing means being operative to restore an element rotated in the last-named manner to its slot-forming position upon the arrival of said vane at its normal position for reception in said slot.

References Cited in the le of this patent UNITED STATES PATENTS 1,494,061 Christiansen May 13, .192A 1,876,438 Werner Sept. 6, 1932 2,235,381 McCormick Mar. 18, 1941 2,452,293Y DiGiovanni Dec. 9, 1941 2,481,124 Kruger Sept. 6, Y1942 2,687,172 Norman Aug. 24, 1954 2,687,455 Norman Aug. 24, 1954 

